I'm assuming you are referring to slow cranking of the engine when starting. Three issues can cause this that are simple. The first and least likely is very high compression. The second is your starter motor is failing, the third and most likely is your battery is either beginning to fail, or your charging system is not fully charging the battery. Clean your battery posts, and start your engine with a voltmeter, check the voltage at the battery. It should read 13.5 or above. If not your issue is the alternator. If so, then shut down the engine and check the battery voltage, it should be around 12.5 or above. If not your battery is shot. If so, take your vehicle to a shop and ask them to check the cranking amperage of the battery. If the battery and charging system are good then it is probably the starter. Notice that I mentioned to clean the battery posts. This is very important. Many times bad connections thete can cause the entire issue.
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I'm assuming you are referring to slow cranking of the engine when starting. Three issues can cause this that are simple. The first and least likely is very high compression. The second is your starter motor is failing, the third and most likely is your battery is either beginning to fail, or your charging system is not fully charging the battery. Clean your battery posts, and start your engine with a voltmeter, check the voltage at the battery. It should read 13.5 or above. If not your issue is the alternator. If so, then shut down the engine and check the battery voltage, it should be around 12.5 or above. If not your battery is shot. If so, take your vehicle to a shop and ask them to check the cranking amperage of the battery.
If the battery and charging system are good then it is probably the starter.
Notice that I mentioned to clean the battery posts. This is very important. Many times bad connections thete can cause the entire issue.